package cn.mulanbay.gateway.handler;

import com.alibaba.fastjson.JSON;
import cn.mulanbay.common.bean.ResultBean;
import cn.mulanbay.gateway.GateWayErrorCode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.web.reactive.error.ErrorWebExceptionHandler;
import org.springframework.cloud.gateway.support.NotFoundException;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.annotation.Order;
import org.springframework.core.io.buffer.DataBufferFactory;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.web.server.ResponseStatusException;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

/**
 * 网关统一异常处理
 *
 * @author fenghong
 */
@Order(-1)
@Configuration
public class GatewayExceptionHandler implements ErrorWebExceptionHandler {

    private static final Logger log = LoggerFactory.getLogger(GatewayExceptionHandler.class);

    @Override
    public Mono<Void> handle(ServerWebExchange exchange, Throwable ex) {
        log.error("网关异常",ex);
        ServerHttpResponse response = exchange.getResponse();
        if (exchange.getResponse().isCommitted()) {
            return Mono.error(ex);
        }
        ResultBean rb = null;
        if (ex instanceof NotFoundException) {
            rb = new ResultBean(GateWayErrorCode.SERVICE_NOT_FOUND,"服务未找到");
        } else if (ex instanceof ResponseStatusException) {
            //ResponseStatusException responseStatusException = (ResponseStatusException) ex;
            rb = new ResultBean(GateWayErrorCode.RESPONSE_STATUS_ERROR,ex.getMessage());
        } else {
            rb = new ResultBean(GateWayErrorCode.INNER_ERROR,"内部服务器错误");
        }

        log.error("[网关异常处理]请求路径:{},异常信息:{}", exchange.getRequest().getPath(), ex.getMessage());
        response.getHeaders().setContentType(MediaType.APPLICATION_JSON);
        response.setStatusCode(HttpStatus.OK);

        ResultBean finalRb = rb;
        return response.writeWith(Mono.fromSupplier(() -> {
            DataBufferFactory bufferFactory = response.bufferFactory();
            //log.debug("error:"+JsonUtil.beanToJson(R.fail(ex.getMessage())));
            return bufferFactory.wrap(JSON.toJSONBytes(finalRb));
        }));

    }
}
